My 2015 clock (on touchscreen radio display) intermittently loses the clock setting (resets to 12:00 or 1:00) and last radio station especially if it sits (garaged) for a while. Toyota hasn’t been able to fix it by updating software, replacing entire radio assembly 3 times and inspect wiring/ connectors from fuse box to radio. Battery voltage always checks 12.6 V or more static. Any ideas?
My Corolla was doing the same thing last year. I replaced the battery and it solved the problem. In your case, I would clean the battery terminals and make sure they are tight. Let us know how you did,
I had the same problem with a 1990 Ford Aerostar. The clock would reset to 12:00. I just ignored it since I go back to the days when a car clock was only right twice a day. I should have investigated the cause. I stopped at a station to fill the gas tank and when I tried to start the Aerostar, there was no power. The lights wouldn’t come on. I checked the battery connections and they were fine. I called AAA and the van wouldn’t even start with a jump. I had the van towed to my house and took our other vehicle to Walmart, came back home and installed the new battery. The vehicle started immediately and I had no more problems. The old battery was so far gone that the vehicle couldn’t be started with a jump. I think that when the battery voltage drops below a certain point, the clock won’t operate.
When you drive, do you make only short trips? Is this your original battery? Has anyone checked for a parasitic draw?
Your battery is 3 to 4 years old now. I find I need to replace mine after about 4 years. If nothing else works, try replacing the battery.